Using 1/4 tsp of Flora Danica in 2 gallons of milk, 4:1 PC:Geo (New England Cheesemaking strains) and the same blue mold I used for my Stilton approximation (culled from a commercial cheese I like, emulsified in some water before adding to the milk with the cultures.

Here's where I am so far (cultures and molds added ready to stir in) :

Interesting - I mixed PC and Geo in the milk along with a blue slurry. Expecting to have to use Bob's hot water dip and spray method, I found that the PC and Geo are totally dominant on the exterior, no washing required. Here they are after multiple skewerings hoping to get some internal blue development.

I can recommend them! It's a delicious tasting cheese. IMHO the best way to prevent blue on the outside is not to add the PR to the milk, but to fill the moulds to the half with the curd and then to sprinkle the PR-dust over the curd, making sure not to sprinkle at the outside. Then fill the moulds with the rest of the curds. This way you're almost sure not to have blue at the outside, especially when you wait with piercing until the Geo and/or PC developed well at the rind.

It's long since gone, but this make turned out to be just a nice Camembert. I'll try again and not add PC to the milk, but spray it on after the blue has formed and the wheels get pierced. Another learning experience.

The trickiest aspect of these cheeses is getting the blue to grow inside what is normally, a very soft cheese. Maintaining some oxygen spaces inside the cheese to allow the blue to grow, without the cheese collapsing around the holes can be difficult. Herman's option of adding the PR into the center of the cheese during the make, which seems to be used by a number of people on the forum, will help, but you still need to get the piercing right and keep the piercing holes open. I found the drier curd helped a lot, but obviously too dry and its hard to get the soft gooey interior.

Keep experimenting, take lots of notes to help with fault finding, and you will get the balance right. Good luck